Research projects in progress

Project manager: Kristjan Ait, Estonian University of Life Sciences
Duration of the project: 2026-2028
RMK funding: EUR 215,000
Main project contributors: Kristjan Ait, Heino Õunap, Floortje Vodde, Kristiina Palm-Hellenurm, Argo Orumaa

Bark beetle damage accounts for an estimated 17% of all forest damage in Europe, and its share has doubled over the past 20 years. In Estonia, too, the area affected by bark beetle damage has increased sharply since the dry summer of 2018.

The spruce bark beetle (Ips typographus) is usually considered the primary pest in spruce stands, but previous studies have shown that a significant proportion of trees are also infested with the northern bark beetle (Ips duplicatus). In 2024, the complete development of two generations of the northern bark beetle was observed in study areas in Võru County, whereas previous knowledge indicated that this species produces only one generation per year. This may indicate a change in the species’ behavior under warming climate conditions.

The aim of the project is to clarify how the bark beetle behaves in Estonia – whether it regularly produces multiple generations and where it hibernates (under tree bark or in the soil). The study combines monitoring with pheromone traps, field observations at damage sites, and analysis of bark samples, and compiles risk assessments based on temperature data. The results will provide a basis for updating forest protection recommendations and support evidence-based decision-making regarding the protection of spruce stands.

Project manager: Kuno Kasak, Tartu University
Duration of the project: 2026 – 2028
RMK funding: 110 000 €
Main project contributors: Kuno Kasak, Margit Kõiv-Vainik, Reti Ranniku, Jürgen Sarjas, Joosep Truupõld, Mihkel Pindus

The reconstruction of drainage systems in well-drained peatland forests is necessary to maintain the growth and quality of timber resulting from previous drainage. At the same time, there is little long-term data on how the reconstruction of drainage systems affects water quality. The results of the previous study (2022–2025) indicated that conventional water protection measures (sediment basins and treatment ponds) did not manage the load as expected during the reconstruction work in the short term.

Therefore, the objective of this follow-up project is to assess, through long-term monitoring, how reconstructed ditches affect water quality and how effective sedimentation basins and sedimentation basins combined with treatment ponds are at retaining nutrients, organic matter, and sediments. Monitoring will be conducted in four areas reconstructed in 2024, continuously measuring water levels and water properties and regularly analyzing water samples before and after water protection structures. The results will provide practical recommendations for selecting suitable water protection solutions in well-drained peatland forests.

Project leader: Veiko Uri, Estonian University of Life Sciences
Duration of the project: May 2025 – April 2028
RMK funding: €321 000
Main project contributors: Veiko Uri, Mats Varik, Mai Kukumägi, Kristiina Aun, Marek Uri, Agnes Sepaste

Approximately 16% of Estonia’s forests are drained peatland forests, developed as a result of extensive forest drainage. RMK manages about 205 000 hectares of these forests. Darinage enhances forest productivity, but the decomposition of peat soils releases significant amounts of CO2, potentially turning these forests into carboun sources – especially following clearcutting, which is used to regenerate drained peatland forests.

The goal of this project ist o assess whether the increased productivity and CO2 uptake in drained peatland forests can ofset greenhouse gas emissions resulting from harvesting and soil decomposition. The project will examine changes in carbon balance across different site types and analyze how tree species and site conditions jointly affect post-clearcutting carbon Dynamics. Based on the results, silvicultural recommendations will be developed for selecting suitable tree species, along with guidelines for managing drained peatland forests in a more climate-friendly manner.

In addition, the project will analyze the costs of reconstructing and maintaining drainage systems and evaluate their impact on forest management economics and productivity.

Project leader: Jürgen Aosaar, Estonian University of Life Sciences
Duration of the project: September 2025 – February 2026
RMK funding: €50 000
Main project contributors: Jürgen Aosaar, Paavo Kaimre, Kalev Jõgiste, Tiia Drenkhan-Maaten, Eneli Põldveer, Kristjan Ait, Allar Padari, Mikko Buht, Pille Tomson, Raul Rosenvald, Leho Tedersoo, Liina Remm, Liis Kuresoo, Maie Kiisel, Raimo Pajula, Mati Ilomets

Despite increasing public demand to implement continuous cover forestry (CCF) as an alternatiive to clearcutting, domestic research and empirical data on CCF management are limited. There is a lack of knowledge and long-term experience regarding to the technical implementation of selective cutting and its broader impact on stand development.

This project aims to take the first steps by providing recommendations for transitioning from rotation-based to continuous cover forestry. In the future, this information will allow for the establishment of demonstration and experimental sites across all common site types and tree species.

The project gains additional value from the collaboration between research groups from different universities, who will work together to establish shared principles for CCF.

Project manager: Ülo Mander, University of Tartu
Duration of the project: 2023-2025
RMK funding: EUR 250,000

There are approximately 10,000 hectares of abandoned milled peatlands in Estonia, a quarter of which have been recommended for afforestation. Due to the deficits of phosphorus and potassium in the residual peat, unfavourable microclimate, etc., a large part of the cut-over peatlands remain unvegetated even 30 years later, resulting in high CO2 emissions and increased fire hazard.

The project seeks solutions for cut-over peatland management to maximise carbon sequestration and reduce greenhouse gas emissions. To this end, the success of afforestation of cut-over peatland with different tree species shall be assessed; greenhouse gas emissions, soil temperature, acidity and moisture content, and the groundwater level will be measured; soil samples will be collected, etc.

In the Nordic countries, nutrient-rich wood ash has been used to promote the growth of vegetation cover in cut-over peatland, as it has been found that a lack of nutrients influences the growth of trees, and not so much late spring frosts, droughts, high summer temperatures on dark peat surfaces, short-term excess water, etc. The effect of wood ash on plant growth will also be tested during the project.

Project manager: Kuno Kasak from the University of Tartu
Duration of the project: 2022-2025
RMK funding: EUR 150,000

Estonia’s forests are characterised by their high proportion of bog soils and excessively moist mineral soils. In many regions, it is essential for silviculture and forest management to regulate the water regime of the soil and to maintain the functioning of land improvement systems through reconstruction.

To reduce the negative impact of these works on the aquatic environment, water protection measures must be used. One of the most effective solutions for reducing diffuse pollution is vegetated open water constructed wetlands, or filter beds, which, in addition to calming the water flow, support sedimentation and the biological removal of nutrients.

The project will examine how the renovation of drainage ditches in drained peatland forests affects the quality of surface water, and the use of a filter bed and sedimentation pond along with a traditional sedimentation pond will be compared.

The study will be carried out with land improvement systems to be reconstructed in Western Estonia, which are located in Rumba’s drained peatland forests and flow into the Vigala River. A total of eight water protection measures will be established: six as a ‘normal” solution, i.e. as sediment ponds, and two as hybrid systems (a sediment pond with a filter bed).